Fluorine-containing polymers may be expected to provide various properties such as weather resistance, heat resistance, chemical resistance, low refractive property, low dielectric property, water- and oil-repellency, and lubricity. These properties are derived from fluorine atoms. Generally, the higher the fluorine content in the polymers is, the more the above properties are expected. However, in the case of aliphatic fluorine-containing polymers, adverse effects are also caused, as the fluorine content increases. For example, the solubility to general organic solvents decreases to cause a deteriorated handling property or the intermolecular force decreases to cause a deteriorated adhesion property to other base materials. To solve these problems, in order to arbitrarily adjust the fluorine content or the main chain structure of the polymers to obtain a desired property, a method of producing a more versatile fluorine polymer has been desired.
Methods of producing an aliphatic fluorine-containing polymer having an adjusted fluorine content may include, for example, a method of copolymerizing of a fluorine-containing olefin (e.g., tetrafluoroethylene, hexafluoropropylene, and perfluorovinyl ether) and vinyl ether; and a method of polymerizing of fluorine-containing acrylate. However, in these cases, a property adjustment by the main chain structure of the polymer was difficult. On the other hand, a method has been known in which an addition reaction of a fluorine-containing-terminal diene and a fluorine-containing diol in the presence of alkali is used to synthesize a fluorine-containing ether-series polymer (see, for example, U.S. Pat. No. 3,391,118). In this method, it is considered that the fluorine content and the main chain structure of the polymers can be in principle adjusted in a relatively-wide range when the fluorine-containing diene and the fluorine-containing diol can be obtained. However, the synthesis of the fluorine-containing-terminal diene is not always easy. In addition, in order to reduce the generation of byproducts and to obtain a polyaddition polymer having a high-molecular weight and a high solvent solubility, an addition reaction of an elementary reaction must progress quantitatively. However, the addition reaction of the perfluoro-terminal olefin with alcohol under a basic condition causes elimination of hydrogen fluoride (HF) and thus is not always a clean reaction (see, for example, Journal of Fluorine Chemistry, 26, 457-465 (1984)). Thus, in order to reduce the generation of byproducts, to simply obtain a polymer having a high-molecular weight and a high solvent solubility by an addition reaction of the fluorine-containing-terminal diene with the fluorine-containing diol, and to adjust the fluorine content and the main chain structure of the polymers in a wide range, the structure and the reaction conditions of the fluorine-containing-terminal olefin must be further improved.